1. Field of the Invention
The present invention relates to a method of molding a design in low relief into a printing ink containing a puffing agent which has been placed on the fabric. A molding die with a reverse impression of the design to be molded into the ink under heat and pressure is applied to ink with the puffing agent to produce the molded design into the ink.
2. Background of Embellishing Fabrics With Designs
A number of different methods have been used to embellish fabrics with designs, particularly clothing made from cotton such as T-shirts and sweatshirts. Multi-color designs have been printed on T-shirts and sweatshirts by screen printing for some time. These designs have made these articles of clothing very popular. The designs can be printed with a single color or with several colors. Designs with logos and natural scenes have been especially popular. Screen printing suffers from the disadvantage that the amount of ink required on dark garments makes the design rough to the touch on the front of the garment. This roughness can also be frequently felt on the back of the garment as well, which is particularly objectionable if the garment is worn next to the skin. Consumers like to have a garment that has a soft feel or hand on both the front and the back. Attempting to impart a soft feel or hand to a garment has placed a severe limitation upon the type of designs that can be screen printed on garments that have been dyed a dark color.
There has been an interest for some time in making designs in relief (i.e., three dimensional) on garments. One approach that has been used is to emboss a design into a garment. In embossing, a backing is first placed on the back of the fabric in the area that is to be embossed. This backing is usually made of an adhesive coated fabric. A die with the desired design in relief is pressed down on the fabric under heat to stretch the fabric into proper position which the backing helps hold in proper place. Embossing is a slow process as the die must be pressed on the fabric for a relatively long time before the design becomes set. While embossing can be used to produce an attractive design, it suffers from several disadvantages. The projections on the embossing die actually stretch the fabric and backing into relief. This stretched fabric and the backing can result in irritation to the skin of the person wearing the fabric made into a garment. The front of the garment that is embossed does not have a very soft hand either. This means that the fabric does not feel soft as the hand is being lightly rubbed over it. The types of designs that can be embossed are limited in that resistance of the fabric, and especially the backing material, does not permit embossing designs that have sharp corners and angles. Thus, embossing is limited to designs with gentle and rounded curves. Emboss backing materials can cause problems in the washing and care of the garment.
Embossing can be coupled with screen printing to produce an attractive design, but the combination suffers from a number of disadvantages. The embossing itself results in the garment not having a soft hand. The amount of ink used in screen printing can also result in the garment not having a soft hand as it builds up on the surface. While the combination may produce an attractive design, it does not meet the demands of consumers in that the garment is not comfortable to wear because it does not have a soft hand.
The combination of screen printing and embossing is a time consuming process. The embossing itself requires a considerable amount of time to stretch the fabric and lock it into the desired relief position resulting in low productivity.
Another disadvantage of embossing is that the recessed areas cannot be easily printed with ink. It is a very time consuming and expensive process. If the ink is printed on prior to embossing, it tends to crack in the recessed areas as it does not stretch like the fabric stretches. This will result in an unappealing design. If it is done after embossing, it must be done by hand which is time consuming and expensive.
Another disadvantage of embossing is that washing and garment care is more difficult because of the presence of backing material. The thickness of the embroidery makes washing and garment care more difficult.
There is considerable demand for new types of designs for T-shirts and sweatshirts. In particular, consumers would like to have a T-shirt or a sweatshirt with a multi-color design in low relief that has a soft hand on both the back and the front of the fabric. Consumers also want garments that hold up in repeated washing and retain a strong appeal.
3. Prior Art
U.S. Pat. No. 4,845,778, issued on Jul. 11, 1989 (Peterson) discloses a child's garment having a design made of a heat settable material which has been caused to rise slightly above the surface of the garment. This design is for the purpose of providing an anti-skid surface, especially in the knee area. The material providing the anti-skid surface is printed or painted upon the garment and upon curing expands to form a raised surface. This patent mentions a product sold under the tradename "Puffy Pen". This patent also discloses an alternate construction in which the pad is made from a fabric, plastic or other material which can be embossed or formed with a roughened surface to increase the friction as a child crawls. This patent does not disclose or suggest the use of an ink containing a puffing agent and using a molding die to form a design in relief.
U.S. Pat. No. 4,933,991, issued on Jun. 19, 1990 (Love) teaches a dress shirt having printed on the front a dyed portion in the shape of a tie. This portion is printed with a "puffed" ink to provide depth and bulk. The ink is applied artistically to create the design and allowed to dry. Heat is then applied by an iron or oven to cure the ink causing the design to rise up or puff. This patent does not disclose that a molding die may be used to produce a design in relief in the ink.